We all know that eating the right foods is key to maintaining optimum health. In fact, more than 9000 scientific studies have been conducted to document the effects of different types of food on our health and they show that food is actually our best medicine! According to Jean Carper, a best selling author and contributing editor to USA Weekend health section, science has proven that these ten foods can make you healthier and help you live longer:

1. TOMATOES. These are a major source of the strong antioxidant lycopene. Lycopene reduces the risk of can cer by 40% - notably prostate, lung, and stomach can cers - and increases can cer survival. Tomato eaters function better mentally in old age and suffer half as much heart disease. Concentrated tomato sauces (found on pizza and in pasta sauces) have five times more lycopene than fresh tomatoes and canned tomatoes have three times more than fresh.

2. OLIVE OIL. It is a major part of a Mediterranean diet, shown to help reduce death from heart disease and can cer. Heart attack survivors on a Mediterranean diet had half the death rates of those on an ordinary low-fat diet, recent research shows. A famous researcher, Ancel Keys, once declared olive oil the main dietary reason for remarkably low mortality rates among Mediterranean populations. Olive oil, unlike other vegetable oils, is high in antioxidant activity.

3. RED GRAPES. This includes red grape juice and wine. Certain red grapes have moderate antioxidant power. However, purple grape juice tops other juices in antioxidant activity, having four times more than orange or tomato juice. Red wine has about the same antioxidant capacity as purple grape juice or tea. French research shows that drinking red wine in moderation increases longevity.

4. NUTS. These are one of our early evolutionary foods and ultra-compatible with survival. Recent Harvard University research found that eating more than 5 ounces of nuts a week cut heart attack deaths in women by over 40% and helped prevent deadly irregular heartbeats in men. Almonds and walnuts lower blood cholesterol. Nuts are high in fat, but most is good-type monounsaturated and/or omega-3 fatty acids.

Unsalted, fresh nuts are the best kind.

5. WHOLE GRAINS. The more whole grains you eat, the lower your odds of death, a new University of Minnesota study suggests. Middle-aged women who ate slightly more than one whole-grain food per day had a 15% lower death rate than women eating lots of refined processed grains. That calls for more whole-grain dark bread and cereals such as "all bran" and "old-fashioned" oatmeal. Whole grains contain anti-can cer agents and help stabilize blood sugar and insulin, which may promote longevity.

6. SALMON & OTHER FATTY FISH. These contain high amounts of the type of fat - omega-3 fatty acids - that performs miracles throughout the body, fighting virtually every chronic disease known. Without it, your brain cannot think, your heart cannot beat properly, your arteries clog, and your joints become inflamed. You need at least an ounce a day or two servings of fatty fish a week. Both red and pink canned salmon, sardines, mackerel, herring, and tuna are rich in the essential omega-3's.

7. BLUEBERRIES. One of the best antioxidant-rich foods, say Tufts University researchers. Blueberries are so powerful in retarding aging in animals that they can block brain changes leading to decline and even reverse failing memory. How much should be eaten? The human equivalent of the amount used in animal studies is a half-cup of frozen or fresh blueberries a day.

8. GARLIC. This herb is packed with nutrients known to help fend off can cer, heart disease, aging, and other health problems. Garlic has prolonged can cer survival time and extended animal lifespans by about 5%, which in humans might add about four years, German researchers have found. A tip from researchers at Penn State: let crushed garlic "rest" about ten minutes before cooking it, to preserve its disease-fighting agents.

9. SPINACH. This super health-promoter is second among vegetables only to garlic in antioxidant capacity. It is also rich in folic acid, which helps fight can cer, heart disease, and mental disorders. In animals, it protects aging brains from degeneration, according to studies performed at Tufts University. New University of Kentucky research shows folic acid may help prevent Alzheimer's Disease. Both raw and steamed spinach contain high antioxidant and other essential nutrient content.

10. TEA. Green and ordinary black tea pack the same amounts of antioxidants and have equal benefits, experts say. Harvard researchers recently found that drinking one cup of black tea a day cut heart-disease risk in half. Be sure to make ice tea from loose tea or tea bags; instant tea and bottled teas contain minimal antioxidants, tests at Tufts University show.

Twenty-four hundred years ago, Hippocrates, the "father of modern medicine" said, "let food be your medicine and let medicine be your food." Today, there is overwhelming scientific evidence to suggest that Hippocrates was right on the mark!